Godot uses SCons to build. We love it, we are
not changing it for anything else. We are not even sure other build
systems are up to the task of building Godot. We constantly get requests
to move the build system to CMake, or Visual Studio, but this is not
going to happen. There are many reasons why we have chosen SCons over
other alternatives, for example:

Godot can be compiled for a dozen different platforms. All PC
platforms, all mobile platforms, many consoles, and many web-based
platforms (such as HTML5 and Chrome PNACL).

Developers often need to compile for several of the platforms at
the same time, or even different targets of the same platform. They
can’t afford reconfiguring and rebuilding the project each time.
SCons can do this with no sweat, without breaking the builds.

SCons will never break a build no matter how many changes,
configurations, additions, removals etc. You have more chances to die
struck by lightning than needing to clean and rebuild in SCons.

Godot build process is not simple. Several files are generated by
code (binders), others are parsed (shaders), and others need to offer
customization (plugins). This requires complex logic which is easier
to write in an actual programming language (like Python) rather than
using a mostly macro-based language only meant for building.

Godot build process makes heavy use of cross compiling tools. Each
platform has a specific detection process, and all these must be
handled as specific cases with special code written for each.

So, please try to keep an open mind and get at least a little familiar with it if you are planning to
build Godot yourself.

Note that for Windows/Visual Studio, you need to use x86_x64CrossToolsCommandPromptforVS2017 or similar, depending on your install, instead of the standard Windows command prompt to enter the commands below.

Godot’s build system will begin by detecting the platforms it can build
for. If not detected, the platform will simply not appear on the list of
available platforms. The build requirements for each platform are
described in the rest of this tutorial section.

SCons is invoked by just calling scons.

However, this will do nothing except list the available platforms, for
example:

This will start the build process, which will take a while. If you want
scons to build faster, use the -j<cores> parameter to specify how many
cores will be used for the build. Or just leave it using one core, so you
can use your computer for something else :)

This means that the binary is for X11, is not optimized, has tools (the
whole editor) compiled in, and is meant for 64 bits.

A Windows binary with the same configuration will look like this.

C:\GODOT> DIR BIN/
godot.windows.tools.64.exe

Just copy that binary to wherever you like, as it contains the
project manager, editor and all means to execute the game. However, it
lacks the data to export it to the different platforms. For that the
export templates are needed (which can be either downloaded from
godotengine.org, or you can build them yourself).

Aside from that, there are a few standard options that can be set in all
build targets, and which will be explained below.

Tools are enabled by default in all PC targets (Linux, Windows, macOS),
disabled for everything else. Disabling tools produces a binary that can
run projects but that does not include the editor or the project
manager.

release_debug: Build without C++ debugging symbols and
optimization, but keep the runtime checks (performs checks and
reports errors). Official binaries use this configuration.

release: Build without symbols, with optimization and with little
to no runtime checks. This target can’t be used together with
tools=yes, as the tools require some debug functionality and run-time
checks to run.

scons platform=<platform> target=debug/release_debug/release

This flag appends the “.debug” suffix (for debug), or “.tools” (for debug
with tools enabled). When optimization is enabled (release) it appends
the “.opt” suffix.

Official export templates are downloaded from the Godot Engine site:
godotengine.org. However, you might want
to build them yourself (in case you want newer ones, you are using custom
modules, or simply don’t trust your own shadow).

If you download the official export templates package and unzip it, you
will notice that most are just optimized binaries or packages for each
platform:

To create those yourself, just follow the instructions detailed for each
platform in this same tutorial section. Each platform explains how to
create its own template.

If you are developing for multiple platforms, macOS is definitely the most convenient
host platform for cross compilation, since you can cross-compile for
almost every target (except for UWP). Linux and Windows come in second
place, but Linux has the advantage of being the easier platform to set
this up.